.\" $NetBSD: cproj.3,v 1.2 2010/09/15 18:40:27 wiz Exp $
.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved
.TH "CPROJ" 3P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual"
.\" cproj
.SH NAME
cproj, cprojf, cprojl \- complex projection functions
.SH SYNOPSIS
.LP
\fB#include <complex.h>
.br
.sp
double cproj(double complex\fP \fIz\fP\fB);
.br
float cprojf(float complex\fP \fIz\fP\fB);
.br
long double cprojl(long double complex\fP \fIz\fP\fB);
.br
\fP
.SH DESCRIPTION
.LP
These functions compute a projection of \fIz\fP ono the Riemann sphere:
\fIz\fP projects to \fIz\fP , except that all complex infinities (even those
with one infinite part and one NaN part) project to positive infinity on the
real axis. If \fIz\fP has an infinite part, then cproj(z) shall be equivalent to:
INFINITY + I * copysign(0.0, cimag(z))
.SH RETURN VALUE
.LP
These functions return the value of the projection onto the Riemann sphere.
.SH ERRORS
.LP
No errors are defined.
.LP
\fIThe following sections are informative.\fP
.SH EXAMPLES
.LP
None.
.SH APPLICATION USAGE
.LP
None.
.SH RATIONALE
.LP
None.
.SH FUTURE DIRECTIONS
.LP
None.
.SH SEE ALSO
.LP
\fIcarg\fP(), \fIcimag\fP(), \fIconj\fP(), \fIcreal\fP() the
Base Definitions volume of IEEE\ Std\ 1003.1-2001, \fI<complex.h>\fP
.SH COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online at
http://www.opengroup.org/unix/online.html .